When Mark Russell gets a grant, look out. Freshly released from his curatorial position at the Lower East Side’s P.S. 122, he produced this weekend’s “Under the Radar” festival at St. Ann’s Warehouse, a highlight reel of off-off-Broadway that showcased underrated, relatively undiscovered gems. If you really committed yourself to spending a few days in DUMBO, you could catch up on everything important you missed this year.

Saturday at St. Ann’s, the show that out-sold, out-packed, and out-performed everything else was the return of the Civilians. The company’s “Gone Missing,” a paean to nostalgia and the magic of lost things, has been touring and garnering praise on both sides of the Atlantic. Tonight is another rare chance to see Steve Cosson’s delicious take on documentary theater in its prime example so far.

Six versatile company members perform slivers of interviews about missing objects. They become grandmothers reminiscing about lost necklaces, a cop ruminating on the various things that disappear from DOAs, and an expert holding forth on “dispose-a-phobics.” The interviewers rigorously keep their subjects to task – people can’t talk about jobs, or people, or love. So interspersed throughout, Michael Friedman’s songs address these more profound losses in every genre imaginable. The ensemble, like the songs, bounces between quiet sincerity and deadpan humor, never letting the mood of the show stabilize before zooming into the next number.

In the same space at St. Ann’s that afternoon, two of Mr. Russell’s West Coast favorites took the stage. Marc Bamuthi Joseph, a familiar face from “Russell Simmons’s Def Poetry Jam,” performed his “Word Became Flesh,” a slam-tacular autobiographical discussion of fatherhood, complete with modern dance breaks and shout-outs to his 3-year-old son.

Speaking just as quickly, Herbert Siguenza arrived with “Cantinflas!,” an homage to Mario Moreno, “the Charlie Chaplin of Mexico.” Neither of them particularly exceeded the usual limitations of the one-man show, but both are impressive performers.

Leaping and spinning, running in place and around the stage, Mr. Joseph doesn’t hold an iota of his physical energy in reserve. His 12-movement spoken-word aria is basically a letter addressed to the heartbeat of an unborn son. Unflinchingly confessional, Mr. Joseph discusses the infidelity that led to his son’s conception, the ambivalence of a man on the verge of fatherhood, and the ways cowardice masquerades as a desire for freedom.

Mr. Joseph addresses the fear he already has for another “brown boy” emerging into a racist world, and the regret he feels that his beloved hip-hop culture has turned into “danceable misogyny.” Clearly, he’s throwing his net wide, but his poetry steps to the next level in a movement on “The Nigger Mentality” – a strange, terrifying section in which he embodies the meeting between luscious Capitalism and tough-guy Racism. Their child, Slavery, will in turn spawn Nigger Mentality, and Mr. Joseph lets that creature out of the box to have his self-hating, disturbing say.

Mr. Siguenza’s “Cantinflas!” is just as fluent, but, sadly, in a different language. In his artist’s statement, as well as in the show itself, Mr. Siguenza tells us that Moreno’s bizarre brand of linguistic comedy just doesn’t translate. During the few bits in English, it’s clear he is absolutely right. Moreno’s signature tumble of puns, half-meanings, and nonsense will be lost on the non-Spanish speaker. Mr. Siguenza is an incredible actor – his physical assurance as the young and 81-year-old versions of the comic make me want to see anything he’ll dream up. But his hero never succeeded in crossing over to Hollywood, and Mr. Siguenza falls victim to a similar cultural gap.

Several of the pieces will continue on after the festival officially ends this evening. Cynthia Hopkins’s gorgeous “Accidental Nostalgia” has two more weeks at St. Ann’s, and the Foundry will present Kama Ginkas’s “K.I. From Crime” until the end of the month. These are both unmissable – particularly Mr. Ginkas’s dazzling tour de force.

Mr. Ginkas, recognized on the street in Moscow and mobbed by young and old alike, is too little known here. “K.I.,” a strangely comprehensible monologue in Russian, has been his calling card for years. Virtuoso actress Oksana Mysina and Mr. Ginkas both deserve every word of hype spoken about them – including these.

In the meantime, tonight you can see “Gone Missing” at 5 p.m., Big Dance Theater’s “Plan B” (a delightful blend of Nixon’s tapes and German Romanticism) at 7 p.m., or Mr. Joseph at 8 p.m. And if you don’t see them this time, don’t expect to get another second chance.

Until today (38 Water Street at Dock Street, Brooklyn, 718-254-8779).